Dental apparatus



Aug-18,1970 F. E.COCHERELL E AL 3,524,676

DENTAL APPARATUS 5 Sheets-Sheet 1 Filed Aug. 4, 1967 [Nan/r025 #k4n/c/5 i diam/2544 [It-H430 E Chm/2544 e a/wiim g 1-970 F. COCHERELL E AL DENTAL APPARATUS 5 Shets-Sheet 2 Filed Aug. 4.. 1967 Ang.'18,'1970 F. ECOCHERELL ETAL 3,524,676

DENTAL APPARATUS Aug. 18, 1-970 COCHERELL ET AL 3,524,676

' DENTAL APPARATUS I Filed Aug. 4. 1967 5 Sheets-Sheet Jzvmm-azs Femvc/s Chm/254; imwnea 5f Cam/sea; 5y 2/ 41 fix; and W 5 Sheets-Sheet 5 [Mm mes 1 Fem/as f. Com/sea; flap/e0 5 Goa/#52544 Aug. 18, 1-970 F. E. COCHERELL T DENTAU APPARATUS Filed Aug. 4. 1967 in mi %N United States Patent 3,524,676 DENTAL APPARATUS Francis E. Cocherell, 3455 N. Rancho Rio Bonita Road, Covina, Calif. 91722, and Richard B. Cocherell, 363 N. Spinks Canyon Road, Duarte, Calif. 91010 Filed Aug. 4, 1967, Ser. No. 658,457 Int. Cl. A47c 7/62 U.S. Cl. 297-188 22 Claims ABSTRACT OF THE DISCLOSURE This dental apparatus comprises a dental unit integrated with a patients chair. The upper end of the unit incorporates an instrument center or head for mounting any desired selection of dental devices and instruments used in patient treatment and the unit also includes a cuspidor that can be selectively mounted at either side of the instrument head. The base of the apparatus includes a wheeled ring, turnable about a vertical axis, to revolve the unit bodily around the chair to an adjusted position at either side of the chair. The dental unit is shiftable radially with respect to this base ring in order to change the units radius of rotation and so provide another mode of adjustment of the unit with respect to the head of the patient in the chair. Additional modes of adjustment of the dental unit and its instrument head all serve to focus the instrument head and the dental instruments and devices carried thereby into correct position with respect to the patients head to minimize loss of time and motion by the dentist in treating the patient. To this end, the dental unit is independently turnable about a vertical axis, can be swung inwardly and outwardly of the chair on a horizontal pivot axis, includes power means for vertically adjusting the height of the instrument center, and the instrument center is itself independently t'urnable about a vertical axis. The dental chair has an adjustable back whereby the head of the patient can be adjusted to any position on an are contained in a vertical plane. By this means, the dentist places the patients head at the correct angle and elevation for the particular operation or procedure to be performed. Thereafter, through one or several of the modes of adjustment of the dental unit, the dental instrument center or head of the unit is correctly positioned both as regards height and angular position with respect to the patients head so that the dentist, his assistant and all the facilities of the instrument head are properly oriented with respect to the patients head. Latching mechanisms are employed to hold the unit in several of its adjusted positions. All service lines for both the dental devices and for the power means for raising and lowering the instrument head are enclosed within the dental unit and are carried thereby as the unit is swung around the chair. At the lower end of the dental unit, these service lines extend radially inwardly toward a position within the base ring and a service well is provided under the base of the dental apparatus, whereby all service lines can be connected to remote sourcesof power or waste or exhaust.

Typically, dentists offices are provided with dental equipment pedestals which are stationary and in a fixed relationship with respect to the patients chair. On this fixed pedestal are mounted such devices as a cuspidor, saliva ejector, water hoses and syringes, and one or more hand pieces. These and other devices may be, and usually are supported at several different locations on the pedestal and in a variety of different ways. The cuspidor, for example, is usually in a fixed location. Hand pieces may be receivable in sockets formed in the column of the pedestal or a low-speed, belt-driven hand piece may be supported on an overhanging linkage arrangement. Additionally, one

3,524,676 Patented Aug. 18, 1970 "ice or more trays may be mounted for swingable movement relative to the pedestal on broken arms. As a result, the devices and tools to be used by the dentist, his assistant and the patient are in scattered locations. Much lost time results from this arrangement, as, for example, in the separate swinging of supporting arms for trays or hand pieces, handing back and forth between the dentist and his assistant of the several devices, and occasionally, a long interruption of the operation to allow the patients use of the cuspidor. Further, the pedestal is in fixed position on either the left or right-hand side of the chair so that the equipment cannot be used with equal facility by either left or right-handed dentists, and, even when arranged in the correct position for the handedness of the dentist, is inaccessible to him when he stations himself at the opposite side of the chair from the pedestal, as he usually does.

In order to overcome these disadvantages, a variety of devices have heretofore been devised or proposed. However, so far as we are aware, there has not yet been devised a fully integrated patients chair and dental unit wherein all necessary tools are arranged into a compact instrument center with substantially complete freedom of movement into any desired relationship to the patient and dentist. More specifically, our invention provides an integrated patients chair and instrument head, such that all instruments on the head can be freely adjusted into the best position relative to the patient and dentist for performing any given operation with the least amount of lost motion and time. A dental instrument center is orbitally related to a patients chair so as to be usable with equal facility by either left or right-handed dentists, or to be shifted into the correct relationship to both the dentist and patient, irrespective of the left or right-handedness of the dentist and of the side of the chair on which the dentist prefers to work. The unit is shiftable orbitally and laterally with respect to the chair so that the instrument center can be located in the correct position relative to the position of the headrest of the chair throughout the range of adjustment of the chair back. This orbital dental'unit may be employed in combination with any standard chair as a base for the chair, or with specially made chairs structurally integrated with the unit and, in either event, eliminates any exposed umbilical cord connections between the dental instrument unit and its power sources.

The foregoing and other objects and advantages of our invention will appear from the following description of a presently preferred embodiment thereof, in conjunction with the annexed drawings, wherein:

FIG. 1 is a perspective view of a presently preferred embodiment of our dental apparatus;

FIG. 2 is a partial vertical sectional view, the major portion of the patients chair having been removed, to disclose internal details of construction of the dental instrument unit;

FIG. 3 is a perspective view of the movable framework portion of the dental unit;

FIG. 4 is a partial vertical sectional view taken on the line 44 of FIG. 2;

FIG. 5 is a partial sectional view of the base portion of the dental unit taken on the line 5-5 of FIG. 4;

FIG. 6 is a sectional view taken on the line 6-6 of FIG. 2;

FIG. 7 is a partial vertical sectional view of the dental unit with a modified power means for effecting vertical adjustment;

FIG. 8 is a partial perspective view of a conduit arrangement for communicating the service lines between the base of the dental unit and the chair base portion;

FIG. 9 is a top plan view of the instrument center or head of the dental unit, with a portion of the top surface being cut away to reveal interior parts;

3 FIG. is a partial sectional view, on the line 1010 of FIG. 2, of the arrangement for communicating water and vacuum and waste lines with the cuspidor on either side of the instrument head;

FIGS. 1113 are schematic elevational views illustratlng different positions of adjustment and movements of th dental unit with respect to the patients chair;

FIG. 14 is a plan view of the base portion of the apparatus, taken on the line 1414 of FIG. 2, with portions of the top plate cut away to disclose interior details of construction;

FIG. is a partial sectional view on the line 15-15 of FIG. 14; and

FIG. 16 is a partial sectional view on the line 16-16 of FIG. 14.

In general, the dental apparatus comprises a base assembly 10 which supports both a patients chair 11 and a dental unit 12. An instrument center or head 13 surmounts the unit 12 and a detachably connected cuspidor 14 may be connected to the unit adjacent one or the other of opposite sides of the head 13. The instrument center 13 and the instruments thereon can be shifted to any desired position relative to the head of a patient in the chair 11, whether the patient be erect or reclining, because the unit 12 has several modes of adjustment. The dental unit 12 is shiftably radially with respect to the chair and is independently turnable about a vertical axis. The unit 12 is also arcuately swingable about a horizontal axis and can be vertically elongated and contracted. The head 13 can be independently turned relative to the unit 12 about a vertical axis and is self-levelling in all movements of the unit 12. The unit 12 is orbitally swingable around the chair 11, through nearly a full circle that is interrupted only at the toe of the chair, and so can be set at any desired angular position with respect to the head of the patient.

In addition to the chair 11 and dental unit 12, the base assembly 10 also supports a light 15 on a pole standard 16 that is swingably carried by an arm connection 17 to the base assembly 10, under the toe or foot portion of the chair 11. Accordingly, the light 15 may be positioned at either one side or the other of the chair.

More specifically, referring to FIGS. 2 and 14, the base assembly 10 comprises a flat ring 20 of large diameter, say 30 inches, and is provided with a radially projecting integral arm 21. Pivotally connected to the upper surface of the arm 21 is a hollow swing arm 17 on which the lamp pole standard 16 is affixed at the outer end of the arm. If desired, a set screw 22 may be incorporated into the pivotal connection between the arm 17 and arm 21 whereby to hold the lamp standard in desired adjusted position. When the chair 11 is mounted over the base assembly 10, the foot portion of the chair, when locked in operating position, will normally protrude over the integral arm 21 of the bottom ring 20. Electrical conductors 18 for the light extend through the hollow pole 16 and arm 17 and radially through the arm 21 and ring 20 via a suitable channel 19 in the bottom of the ring.

The upper surface of the bottom ring 20 serves as a track for a base ring 23 that is of approximately the same outer diameter as the underlying ring, but of a lesser radial width. As is shown in FIG. 14, the base ring 23 is formed with sets of three slots 24, the sets being angularly spaced apart around the base ring. Referring to FIG. 16, it will be noted that the slots 24 are spanned by radially disposed axles 25, each of the axles supporting a roller 26, and that all of the axles of the set of three are offset to one side or the other of the median plane of the base ring 23. The diameter of the roller 26 is such that each roller protrudes from one side only of the base ring 23. Accordingly, in each set of three rollers 26, at least one of the rollers bears downwardly on the underlying ring 20 while at least one of the rollers protrudes upwardly and bears only against the underside of a cover plate 27. The base ring 23 is thus mounted with clearance between the cover plate 27 and the underlying ring 20 so as to be freely rotatable on the track provided by the underlying ring.

In order to maintain the base ring 23 in coaxial relationship with the underlying ring 20, the latter on its upper surface is provided with a radial thrust bearing arrangement. A pair of blocks 28a and b are affixed to the upper side of the ring 20 adjacent the arm 21 and on opposite sides of a diametral area of projection of the arm 21. These blocks 28a and b may be secured in place by a convenient fastener, as for example, machine screws 29, that also serve to secure the cover plate 27 in fixed relation to the underlying ring 20. The outer edges of the blocks 28a and b are arcuate and formed on a radius to provide clearance between the outer edges of the blocks and the inner edge of the base ring 23. As is shown in FIG. 15, each of the blocks is formed with a slot 30 that opens into the outer edge of the block 28 and is spanned by an axle 31, mounting a roller 32 in rolling engagement with the inner edge of the base ring 23. On the other side of the base ring 23 and on a diameter bisecting the angle included between the blocks 28a and b, the upper surface of the underlying ring 20 mounts an axle 33 which carries a roller 34, also in rolling engagement with the inner edge of the base frame 23, and which cooperates with the two rollers 32 to maintain the base ring 23 coaxially related to the underlying track or ring 20.

For mounting the dental unit 12 onto the base assembly, a platform member 37 is rigidly secured to and extends radially outwardly from the outer edge of the base ring 23. As is shown in FIG. 4, the member 37 is formed on its upper face with a channel 38 which communicates at its inner end with a groove 39 of the same cross-sectional area and configuration as the channel 38 and cut across the upper face of the base ring 23. This channel serves as a guideway for a wheeled frame 36 for the unit 12 as the unit is shifted or adjusted radially with respect to the patients chair. The frame 36 may comprise a vertically spaced pair of plates 40 and 41 rigidly interconnected to spacer blocks 42. As is indicated in FIG. 2, each of the opposite sides of the lower plate 41 mounts a pair of downwardly protruding rollers 43 and a pair of upwardly protruding rollers 44, the former pair bearing on the floor of the channel 38. Each of the opposite edges of the channel 38 is overhung by a rigidly secured strap 45 extending the length of the channel to serve as bearing surfaces for the upwardly protruding rollers 44 at opposite sides of the wheeled frame. The wheeled frame 36 mounts rollers 47 on top of plate 41 that are horizontally arranged to bear against the inner edges of the straps 45. A stop member 46 is secured at the outer end of the channel 38 to prevent the wheeled framework and the unit 12 from being completely withdrawn from the member 37.

The floor 50 of the operating room is formed with a well beneath the base assembly 10 and this well is provided with openings or terminals for connection to the various service lines to be extended into the dental unit 12 and chair 11. The kinds and number of such openings may vary depending upon the kinds of equipment to be incorporated into the unit 12. For example, provision may be made for a vacuum connection 52, electric connection 53, compressed air connection 54, water connection 55, and a drain or waste connection 56, all of which are in turn connected to remotely located vacuum, water, air, or electricity sources, as the case may be, and to a sewer for the drain connection.

In order to establish communication between the various service connections in the well 51 and devices carried in the dental unit 12, a plurality of conduits. are carried on the radially shiftable wheeled frame 36 in the channel 38. These may take the form shown in FIG. 8 of right-angle elbow conduits of rectangular cross-sectional configuration, externally. These may serve as fluid conduits, per se, or to enclose other fluid conduits, or to pass electrical cable and wire therethrough. In any event, one large conduit or an appropriate number of small conduits is provided in accordance with the varieties of service to be incorporated into the dental unit 12. In the illustrated example, there are provided conduits 58a-g having vertical legs around which a band 59 is passed, the opposite ends of the band being'aflixed to the top plate 40. The'lower, horizontally disposed legs of the conduits are received within the channel 38, and as is shown in FIG. 14, extend radially inwardly through the slot 39 of the base ring 23 to terminate adjacent the floor well 51. The conduits 58a-g are thus radially movable with the dental unit 12, and swingable around the patients chair along with the dental unit.

At their inner ends, each of the conduits 58a-g is interconnected withthe appropriate waste or service line by a length of flexible conduit 60 of a size and composition suitable for the service intended. Since twisting of these flexible conduits 60 through more than 360 would be injurious, a stop means is provided to limit orbital movement of the dental unit 12 to less than 360. For this purpose, a pair of stop plates are rigidly aflixed to the inner edge of the base ring 23 at opposite sides of the group of conduits 58a-g, each of the plates 61 being provided with a bumper pad 63. It will be noted in FIG. 15 that the roller 34 is relatively thin in vertical dimension so as to provide sufficient clearance thereabove to prevent obstruction to the plates 61 and 62, and the conduits 58a-g as they are swung thereover.

Referring to FIG. 14, it will be seen that the bumper plate 61 will arrest clockwise movement by abutment with the member 28a, while the bumper plate 62 will stop counterclockwise movement of the dental unit by abutment with the member 28b. By this means, excessive twisting of the flexible conduits 60, such as would result in rupture, is avoided.

The dental unit 12 includes a base'yoke 65, a power cylinder 66, a framework 67, the instrument head 13 and a parallel acting linkage system 68 interconnectin the instrument head and base yoke 65. These parts are functionally interrelated as schematically indicated in FIGS. 11 through 13. Thus, the dental unit 12 as a whole is pivotal on wheeled frame 36 about a vertical axis. The power cylinder 66 is pivotally connected to the base yoke 65 to allow angular movement of the unit as a whole about a horizontal axis. The power cylinder 66 and framework 67 are telescopically related to effect vertical adjustment of the instrument head 13 and, through all phases of movement, the linkage system maintains a substantially horizontal attitude of the instrument head. The instrument head 13 is, in turn, independently pivotable about a vertical axis.

More specifically, the yoke 65 has a bottom member 70 that is integrally formed with an upstanding pair of parallel flanges 71 and 72. As is shown in FIG. 5, a washer 73 is interposed between the yoke 65 and the upper surface of the plate 40 and a fastening means 74 is passed through aligned counterbores in the floor 70 and member 40 whereby to pivotally secure the yoke on the top plate for movement about the axis of the fastener means 74.

Referring to FIG. 4, the power cylinder includes a lower head member 75, a cylindrical body 76 and an upper head member 77. The lower head 75 is integrally formed with a longitudinally projecting boss 78 that is provided with a bore for pivotal connection to a bolt 79 that is secured between the flanges 71 and 72 of the yoke. As FIG. 4 shows, the bolt 79 threadedly mounts a nut 80 as a means of adjustably compressing a helical spring 81 between the nut and a washer 82 that bears against one side of the boss 78. On the other side of the boss 78, a washer 83 is sandwiched between the boss and the yoke flange 72. This arrangement provides an adjustable yieldable friction brake to maintain the dental unit 12 in any desired angle relative to the vertical.

To facilitate swinging the unit 12 upwardly about the pivot bolt 79, a torsion spring 83 is provided between the flange 71 of the base yoke 65 and the boss 78 of the power cylinder. As is shown in FIG. 4, the torsion spring 83 is of relatively large diameter in order to wind with clearance about the pivot bolt 79, nut and compressed spring 81. One end of the torsion spring 84 is hooked in a suitable notch formed in the flange 71 of the base yoke, while the other end of the torsion spring is hooked onto the boss 78 so that'the spring normally biases the power cylinder 66 to vertically erect position. Referring to FIG. 5, a leaf spring 85 has its lower end secured to the floor 70 of the base yoke 65 with its upper end bearing on an edge of the boss 78 in order to yieldably oppose the force of the torsion spring 84 when the unit 12 is swung inwardly towards the patients chair beyond the vertically erect position. It will be understood that the nut 80- is adjusted to secure a nice balance between the force of the torsion spring 84 and the frictional resistance of the washers 82 and 83 on the yoke 78 to allow easy swinging of the dental unit 12 about the pivot bolt 79 while at the same time insuring that the unit is held in the adjusted position.

Referring now to FIG. 3, it will be observed that the rigid framework 67 is provided with a spaced pair of parallel angle iron members that are fixed transversely of the framework and it is to these members 87 that the power cylinder 66 is drivingly connected. As is best seen in FIG. 4, this connection takes the form of a piston rod head 88 aflixed to the outer end of a piston rod 89 and it is secured by fasteners 90 to both of the angle iron members 87. Within the cylinder body 76, the piston rod 89 is secured at its inner end to a piston 91 so that when the piston is raised and lowered by fluid pressures, the framework 67 is correspondingly raised or lowered, thus to eflect vertical adjustment of the instrument head 13. In order to increase the torsional rigidity of the unit 12 when the framework 67 is raised a substantial amount, the upper head 77 of the power cylinder is formed with a boss 92 that is formed with a bore to slidably receive therethrough a rod 93 whose upper end is secured to a boss 94 on the head 88. The lower end of the rod 93 has a collar 95 adjustably secured to it as a means of positively limiting extension of the piston rod short of the maximum stroke of the piston.

The instrument head 13 comprises a boxlike structure which is substantially rectangular in plan configuration. A top 97 of the instrument head is formed with a gen erally rectangular depression defining an instrument tray 98. The rear wall 99 and opposite sidewalls 100 and 101 may be flat straight sheet members but the front wall 102 is preferably concave so that the instruments to be mounted thereon will be arranged on an arc to approximately focus towards the patients head. A bottom 103 of the instrument head 13 is formed with a circular opening 104 so that the various service lines for the equipment to be mounted in the instrument head may be passed into the box or head from the supporting framework 67.

The instrument head is mounted to the supporting framework 67 through a flat bearing plate 106 that is formed with a circular opening 107 to receive a circular flange 108 that is fixed to the opening 104 on the bottom 103 of the head. At opposite sides, the bearing plate 106 is provided with downwardly depending arms 109 whose lower ends are provided with plain bearings 110. Referring to FIG. 3, the upper end of the framework 67 is provided with a pair of plain bearings 111 to register with the bearings 110, whereby to hingedly interconnect the head 13 to the framework 67 by means of a pair of hinge pin 112.

The parallel linkage system '68 comprises a pair of lower links 114, a pair of intermediate links 115, and a pair of upper links 116. As is shown in FIG. 4, the base yoke 65 along one edge mounts an angle iron bracket 117 to which the lower ends of the pair of lower links 114 are pivotally connected. In order to keep these long links 114 in alignment with the power cylinder 66 and so avoid slack in the action of the linkage system, the upper head 77 of the cylinder is formed with a boss supporting a pin 117 in the space between the pair of links. A short bar 118 has its center pivotally connected to the pin 117 and the opposite ends of the bar 118 carry pins 119 each of which extends through an elongated slot 120 formed longitudinally in the confronting portions of the links 114.

The upper ends of the parallel links 114 are pivotally interconnected to opposite horizontal arms of a cruciform crank 121 and on the same side of the crank. On the opposite side of the crank 121, the lower ends of the intermediate links 115 are pivotally interconnected to the opposite vertical arms of the crank 121. Similarly, the upper ends of the parallel intermediate links 115 are pivotally interconnected to the opposite vertical arms of another cruciform crank 122 and on the same side of the crank. The lower ends of the upper parallel links 116 are pivotally interconnected at their lower ends to the opposite horizontal arms of the crank 122 on the opposite side of the crank from the links 115, while the upper ends of the links 116 are pivotally interconnected to a horizontal bracket 123 that is fastened to the underside of the bearing plate 106.

The linkage system 68 functions to maintain the instrument head 13 in a substantially horizontal attitude throughout all movements of the unit 12 and in all adjusted positions of the head. Thus, as is shown in FIG. 11, when the unit 12 is moved from the vertically erect position to the position of FIG. 2, the linkage system 68 maintains the instrument head 13 horizontal. The same result, of course, follows when the unit is swung in the opposite direction as shown in FIG. 12. Similarly, when the power cylinder 66 is actuated to raise the instrument head 13, the linkage system 68 again functions, while straightening out to accommodate the elevation, to maintain the instrument head level.

Dental chairs are commonly provided with electric hydraulic power means to effect raising or lowering or other adjustments of the chair. Accordingly, the chair 11 has a hydraulic cylinder, not shown, adapted to be actuated by the means schematically shown in FIG. 2. These components are mounted within the chair base and typically include a sump or reservoir 125, a conduit 126 communicating the reservoir with a lower end of the hydraulic cylinder of the chair and having an electrically driven pump 127 interposed in the conduit. Another conduit 128 communicates the other end of the chairs hydraulic cylinder to the reservoir 125. The cover plate 27 of the base assembly is adapted to serve as a floor on which to rest the chair 11. The cover late is formed with an opening 129 so that the electrically driven pump 127 can be connected to the electrical connection 53 in the floor well 51 via electrical conduits 130 partially shown in FIG. 2. Appropriate conventional switches and valve controls for the chairs hydraulic cylinder, not shown, are provided at any suitable location on the chair.

If desired, this same hydraulic power system of the dental chair can be employed to operate the power cylinder 66 within the dental unit 12. This may be accomplished in the matter schematically indicated in FIG. 2. Thus, downstream of the pump 127, a lateral conduit means 131 is connected between the conduit 126 and the conduit 58f at the lower end of the dental unit 12. A solenoid controlled valve 132 is interposed in the conduit means 131 and the conduit means is flexible in at least a portion between the valve 132 and the conduit 58]. A flexible conduit 133 extends between the upper end of the conduit 58 and a fitting on the lower cylinder head 75 in order to communicate hydraulic pressure to the underside of the piston 91. At the upper cylinder head 77, another flexible conduit 134 communicates the upper end of the cylinder body 76 with the upper end of the conduit 58.2 at the base of the dental unit. At the inner end of the conduit 58c, another conduit means 135 extends between the inner end of the conduit 58e and the hydraulic reservoir 125 and also includes a flexible portion immediately inwardly of the inner end of the conduit 582. The hydraulic circuit for the power cylinder 66 of the dental unit also includes a by-pass conduit 136 that is controlled by a solenoid actuated valve 137 and which extends between the reservoir 125 and a point in the conduit 131 downstream of the valve 132.

As will be apparent, when the pump 127 is energized and the valve 132 is opened, pressure fluid is admitted to the underside of the piston 91 to effect raising of the framework 67 and the instrument head 13. In order to lower the instrument head 13, the valve 137 is opened in order to bleed fluid from the underside of the piston 91. While not shown, it will be readily understood that the electrically driven pump 127 and the solenoid controlled valves 137 and 132 are controlled by an electrical circuit which will include leads extending into the floor well 51 to the electrical connection 53. Switches for controlling operation of the electric hydraulic system may be located either on the dental chair 11 or on the instrument head 13. In the latter case, the conductors may be passed through the conduit 58a to emerge into the dental unit 12 and up into the head 13 for interconnection to a conveniently located switch or switches on an exposed surface of the head or any other convenient location on the dental unit 12.

FIG. 7 shows an alternative arrangement for actuating the power cylinder 66 of the dental unit by a power means which is independent of the power system of the dental chair 11. In this embodiment, the power cylinder 66 is actuated by com-pressed air. As a result, the hydraulic conduits 58c and f at the base of the unit 12 can be eliminated.

Referring to FIG. 2, an air manifold 138 is rigidly secured to the inside of the framework 67 and a flexible conduit 139 leads from this manifold to the upper end of the compressed air conduit 58b. Referring to FIG. 7 a conduit means 140 extends from the air manifold 138 through a check valve 141 and a solenoid-actuated, normally open valve 142 to the upper end of the cylinder body 76. Another conduit means 143 extends from the air manifold 138 through another check valve 144 and a solenoid-controlled, normally open valve 145 into the upper end of a reservoir 146. This reservoir is also rigidly affixed to the interior of the framework 67 and is partially filled with a volume of hydraulic fluid. A conduit 147 serves to intercommunicate the lower end of the reservoir 146 with the lower end of the cylinder body 76.

The front wall 102 of the instrument head 13 is fitted with an up-switch 148 and a down-switch 149. The upswitch 148 is electrically interconnected by conductors, not shown, to the solenoid controlled valve 142 while the down-switch 149 is electrically interconnected by conductors, not shown, to the solenoid controlled valve 145. It will, of course, now be appreciated that these conductors pass through the interior of the head 13, downwardly through the opening 104 and into the framework 67.

Normally, the conduit means 140 and 143, downstream of the check valves 141 and 144, respectively, are charged with air at a pressure higher than the air pressure upstream of the check valves, whereby both check valves are closed, the piston 91 is stationary, and the instrument head 13 is maintained at a desired elevation. In order to raise the instrument head 13, the up-button 148 is held depressed. This effects closing of the normally open valve 142 while the upper end of the cylinder body 76 is vented to atmosphere through a port in the valve 142. Concurrently, the check valve 144 opens to admit compressed air into the upper end of the reservoir 146, thus to force hydraulic fluid through the conduit 147 to the lower end of the cylinder body to drive the piston 91 upwardly. When the instrument head 13 has reached the desired increased height, the up-button 148 is released whereby the valve 142 is returned to its normally open position. Both check valves 141 and 144 thereupon close and the instrument head 13 stops in the adjusted position.

In order to lower the instrument head 13, the downswitch 149 is held depressed in order to close the normally open valve 145. At the same time, the upper end of the reservoir 146 is vented to atmosphere through an appropriate port in the valve 145. Compressed air is then diverted through the check valve 141 and the normally open valve 142 into the upper end of the cylinder body 76 whereby to drive the piston 91 downwardly and so to lower the instrument head 13. Upon release of the down-button 149, equilibrium is once again established in the opposed air pressures of the system as the check valves 141 and 144 close, after reopening of the valve 145.

While not essential, it is preferable to provide a means to prevent orbital movement, or radial shifting, or turning about a vertical axis of the dental unit 12 while the dentist is performing any operation with a patient. This is accomplished by employing compressed air as the means to efi ect latching of the parts.

Referring to FIG. 5, an air cylinder 150 is affixed between the plates 40 and 41 having a piston operated plunger 151 extending through the top plate 40 for contact with the underside of the yoke 65. A spring, not shown, is mounted within the cylinder 150 to normally bias the plunger 151 downwardly out of contact with the yoke. Thus, when compressed air occupies the space within the cylinder 150 under the piston plunger, the upper end of the plunger 151, which is preferably serrated, firmly holds the yoke 65 and thus the unit 12 against rotation about the axis of the bolt 74.

Similarly, another air cylinder 152 is aflixed between the plates 40 and 41, but this time having a plunger 153 protruding through the bottom plate 41 for contact with the floor of the channel 38. Again, a spring, not shown, normally biases a serrated lower end of the plunger 153 out of contact with the floor of the channel 38. Thus, when compressed air occupies the space within the cylinder 152 above the plunger piston, the serrated end of the rod 153 firmly engages the floor of the channel 38 to prevent radial shifting of the dental unit 12 with respect to the patients chair ill.

A somewhat similar arrangement is employed to prevent orbital movement of the dental unit 12. Referring to FIG. 14, inside of the base ring 23 the underlying ring 20 pivotally mounts at 154, one end of an air cylinder 155. A piston rod 156 protrudes from the other end of the cylinder 155 and mounts a yoke 157 that is pivotally connected to one end of a latch bar 158. The other end of the latch bar is pivotally connected at 159 to the underlying ring 20 adjacent the inner edge of the base ring 23. A spring, not shown, is mounted within the air cylinder 155 to normally bias the rod 156 inwardly in a manner to swing the latch bar 158 clockwise as viewed in the figure to swing the latching end of the bar clear of the inner edge of the base ring 23. Thus, when compressed air is present to oppose the spring pressure, the latch bar 158 is urged in counterclockwise direction and so holds its outer end firmly in engagement with the inner edge of the base ring 23.

For convenience, in adjusting the dental unit 12, all three of these latch mechanisms are preferably operated by a single control. For this purpose, an air manifold 160 is mounted within the framework 67 adjacent to a solenoid controlled valve 161, the two being in communication through a short conduit 162. Another circuit 163 communicates the inlet side of the valve 161 with the first air manifold 140. The air cylinders 150 and 152 located at the base of the unit 12 have hoses 164 and 165, respectively, that extend upwardly into the framework 67 into communication with the manifold 160. The air cylinder that is within the base assembly 10 is also provided with a hose 166 that passes through available space in one of the rigid conduits and so into the unit 12 to also be connected to the manifold 160.

The solenoid valve 161 is normally open whereby compressed air entering the valve from the hose 163 is communicated into the manifold 1'60 and so to all three of the air cylinders 150, 152, and 155, so that all three latch mechanisms are engaged. When the switch 161 is actuated, the source of compressed air through the hose 163 is shutoff and the valve vents to atmosphere whereby all three air cylinders are also vented to atmosphere so that their spring mechanisms become operative to release the latch mechanisms. Operation of the valve 161 is controlled by means of a switch handle 167 taking the form of an elongated bar mounted transversely on the underside of the dental unit head 13. This handle is connected to a normally open switch 168 mounted inside the head 13 and which, in turn, is part of a circuit including the solenoid valve 161. It will be understood that the conductors for the circuit are disposed within the head 13 to pass through the opening 104 and so down into the framework 67 for connection to the solenoid of the valve 161. With this arrangement, so long as the switch handle 167 is depressed, the dental unit 12 can be shifted orbitally with respect to the chair and can also be turned about both horizontal and vertical axes. When the switch handle 167 is released, the compressed air once again becomes effective for latching the apparatus against all three of these movements.

Secured to the outside of the framework 67 of the dental unit, there is a housing 170 which completely surrounds the framework from top to bottom. This housing is preferably made of a rigid or semi-rigid sheet material and at its upper ends is formed with a pair of opposite shoulders 171 and '172. These shoulders are well adapted to receive certain controls and dental devices and so supplement the capacity of the instrument head 13 for supporting a selection of dental instruments. In order that the dental unit 12 may be fully enclosed, a skirt 173 may be secured to the lower end of the housing 170 to hang therefrom. This skirt is generally tubular and preferably made of an accordian pleated flexible or pliable sheet material gathered at its lower end onto a ring 174 which may slidably bear on top of the channel plates 38 of the radial projection 37. A similar arrangement may be employed at the upper end of the housing 170 comprising a generally tubularly shaped and accordian pleated shroud 175 having a lower continuous edge secured to the edge of the opening in the upper end of the housing and having an upper continuous edge secured to a circular flange 176 that is secured to the underside of the bearing plate 106.

Any desired selection of dental instruments and appliances can be mounted in the dental unit 12 with all their service lines completely concealed within the unit. The drawings show an exemplary arrangement which may, for example, include a saliva ejector 180, a high-speed drill 181, a low-speed drill 182 and a 3-way syringe 183, all mounted in the front panel 102 of the head 13. All of these devices may be mounted in the conventional manner with retractable reel mechanisms 184, 185, 186 and 187 staggered and stacked within the hollow instrument head 13. Alignment pulleys 188 are suitably located within the instrument head as guides for the several hose devices 189, each of which serves to interconnect one of the instruments on the front panel 102 with its corresponding reel. The instrument head 113 also mounts a pair of air and water manifolds 190 and 181 within the rear of the instrument head and each of these is interconnected by an appropriate conduit means 192 with one or more of the reels 184 to 187 to provide the correct service for the dental instrument operatively associated with that reel.

The manner of interconnecting such manifolds, reels and dental instruments are all well known in the art and need not be described in detail. However, it is to be realized that the instrument head 113 may be made as large as required to enclose any practical number of reel or other mechanisms and air, water and other manifolds for the number and type of dental instruments to be provided on the front panel 102. Whatever the capacity of the instrument head 13, it is now evident that all electrical wires, fluids, conduits and all manner of service lines may be passed downwardly out of the instrument head 13 into the framework 67 and connected to or extended through appropriate rigid elbow conduits at the base of the dental unit 12 to pass radially inwardly for connection to a suitable connection point or source of supply in the floor well 51.

The cuspidor 14, like the instrument head 13, is selfleveling and, furthermore, can selectively be mounted on either of opposite sides of the dental unit 12 at connections located just above the shoulders 171 and 172 of the housing 170.

The cuspidor 14 is mounted at the outer end of a conventional broken arm 195. The broken arm 195 is hollow throughout its length and at its outer end communicates with the drain opening in the cuspidor 14. At its inner end, the broken arm 195 is provided with a downwardly opening hollow fitting 196 that has communication with a drain passage 197 formed through an elbow fitting 198. The cuspidor 14 also has a water spigot 199 that is supplied through a hose 200 that depends from the broken arm 195 and whose inner end communicates with a water passage 201 extending axially through the elbow fitting 198. The foregoing parts are interconnected as an assembly which assembly as a whole can be mounted to one side or the other of the dental unit 12.

At the upper end and on opposite sides of the framework 67 are a pair of ball bearings 204 in coaxial alignment with each other. Each of these bearings has its outer race rigidly secured to the framework 67 while the inner race of each of these bearings coaxially fixedly receives a tubular member 205. The outer end of each of the members 205 extends outwardly through an opening in the housing 170 and has an enlarged head portion 206 such as is best seen in FIG. 1 overlying the shoulder 171 of the housing. The elbow member 198 is formed with a cup-shaped opening to receive the enlarged head 206 whereby the cuspidor can be supported at either side of the housing. The enlarged head 206 is formed with a central passage 207 adapted for communication with the passage 197 of the elbow fitting 198 and is also formed with a water passage 208 adapted for communication with the passage 201 of the elbow fitting. Each head 206 is also provided with a pair of diametrically opposite locating holes 209 to receive corresponding locating pins, not shown, provided in the cup-shaped opening of the elbow fitting 198 and a set screw may be provided, if desired, to secure the elbow fitting to the head member 206.

Both tubular members 205 have their inner ends received in opposite ends of another heavier tubular member 210 that is provided with a fitting 211 extending radially downwardly therefrom for connection to a hose 212 that may be connected at its lower end to the waste conduit 58g or to the vacuum conduit. By this means, the bowl of the cuspidor 14 is communicated to either waste or vacuum. In order to supply water to the spigot 199 of the cuspidor 14, a pair of water lines 213 and 214 from the water conduit 58c extend into communication with the water passages 208 of the head portions 206. In each of these water lines, there is interposed a manual water shut-off valve 215 whose operating handle is mounted exteriorly on either the shoulder 171 or 172 of the housing 170. By means of the valves 215, water can be selectively turned off or supplied to that side of the housing on which the cuspidor 14 is mounted. The head 206 which is not being used for supporting the cuspidor 14 may, if desired, be covered by an appropriate cap 216, as is shown in FIG. 10.

In order to keep the cuspidor 14 level when the dental unit 12 is swung inwardly and outwardly of the dental chair, a levelling mechanism is provided. As is shown in FIG. 2, this mechanism includes a pair of short links 220 mounted in parallel relation between the large tubular member 210 and a bracket 221 secured to the underside of the bearing plate 106. The short parallel links 220 are thus an extension of the parallel acting linkage system 68 and respond to changes in angle of the dental unit 12 to maintain a level attitude of the cuspidor 14.

A conventional foot pedal drill speed control 225 is operatively interconnected to the drills 181 and 182 in the instrument head 13 by means of a conduit 226 which enters the housing of the dental unit through a grommeted opening 227 in the rear wall of the housing. Control devices of this type are conventional and the parts thereof may be mounted at any convenient place on the framework 67 and within the instrument head 13.

The dental chair 11 has an adjustable back whereby it may be tilted from substantially horizontal to fully upright position and the head of the patient can be positioned at any point within this vertical arc in the vertical plane of movement of the chair back. This adjustability of the chair back in combination with the several modes of adjustment of the dental unit 12 permits placement of the instrument center 13 in the correct position with respect to the patients head in order to minimize loss of time and motion in carrying out operations. The instrument head 13 is adjustable vertically both by actuation of the power cylinder 66 as well as by swinging the dental unit 12 inwardly and outwardly about its horizontal pivot axis. Accordingly, the dental instrument head 13 is adjustable into several horizontal planes intercepting the vertical plane of the arc of movement of the patients head. As the dental unit 12 as a whole is swingable orbital-1y about the chain 11, the instrument head 13 is swingable horizontally in any of its horizontal planes of adjustment. Since the radius of rotation of the unit 12 is adjustable and as the unit can be pivoted downwardly away from the base 10, as in FIG. 12, the unit very readily accommodates a position of the chair back in which the patient reclines horizontally. Further, all of the modes of adjustment of the dental unit 12 are equally available to left or right-handed dentists without making any modification in the dental apparatus.

While preferred embodiments of the invention have been shown and described various modifications thereof will be obvious to those skilled in the art.

We claim:

1. Dental apparatus comprising:

a dental chair having a back that is adjustably tiltable for movement of a headrest on said back through a vertical are in order to position the head of a patient at a desired location on said arc;

a vertically extending dental unit having an instrument head means at is upper end to support a plurality of dental instruments;

a means On said unit for vertically adjusting the elevation of said instrument head means through a plurality of horizontal planes intersecting said vertical arc of movement of said headrest; and a support means for said unit, interconnected to said chair, that is adapted to constrain said unit for planetary motion with respect to said chair in order to move said instrument head means horizontally within each of said plurality of horizontal planes intersecting said vertical arc of movement of said headrest.

2. A dental apparatus as set forth in claim 1 in which said support means includes a means for adjusting the length of the radius of movement of said dental unit.

3. Dental apparatus as set forth in claim 2 in which said means for adjusting said radius includes Wheel and track connections between a lower end of said unit and said support means.

4. Dental apparatus as set forth in claim 2 in which said means for adjusting said radius comprises pivotally interconnected portions of a lower end of said unit and said support means.

5. A dental apparatus as set forth in claim 4 in which said instrument head means for supporting dental instruments comprises a hollow structure mounted on an upper portion of said unit, and in which said unit comprises a lower portion and said upper portion, said upper portion being mounted on said lower portion for vertical movement of said upper portion, said lower portion and said hollow structure being interconnected by a means to translate pivotal movement of said unit into angular movement of said hollow structure with respect to said upper portion in order to maintain a level attitude of said hollow structure. 6. A dental apparatus as set forth in claim 1 in which said chair includes means for vertically adjusting the height of said chair and power means for driving said means to adjust said chair, and in which said vertical adjustment means of said dental unit is adapted to be driven by said power means, said vertical adjustment means of said unit and said power means on said chair being interconnected in part, at least, by a means mounted on and movable with said support means. 7. A dental apparatus as set forth in claim 1 in which at least one connection to a source of power for a dental instrument is positioned beneath said chair, and a power connecting means extends from said connection to the upper end of said dental unit and includes,

(a) a first portion mounted on and movable with said support means and (b) a second portion between said first portion and said connection that is adapted to yield in order to accommodate movement of said power connecting means around said connection as said dental unit is swung horizontally with respect to said chair. 8. A dental apparatus as set forth in claim 7 in which said support vmeans includes cooperating portions adapted to limit horizontal arcuate movement of said support means to less than 360 in order to prevent excessive twisting of said second portion of said power connecting means. 9. A dental apparatus as set forth in claim 1 in which said support means has cooperating stop means adapted to limit horizontal arcuate movement of said dental unit to less than 360. and in which a base for said support means has a horizontally swingable lamp support arm with a vertical pivot axis positioned within that arcuate portion of 360 through which said stop means prevents horizontal arcuate movement of said dental unit, said lamp support arm at its outer end being adapted to support a lamp standard and said lamp support arm axis having a position with respect to said dental chair whereby said support arm can be swung to either side of the chair. 10. A dental apparatus as in claim 1 in which said dental chair and said dental unit are separate units and in which said support means is mounted in an assembly adapted to serve as a floor for said dental chair, said dental chair being seated on said assembly, said dental unit being pivotal ly interconnected at a lower end to said support means for swinging the upper end of said unit radially inwardly and outwardly of said chair. 11. A dental apparatus comprising: a chamber defined within a surrounding wall; a base ring;

means supporting said base ring for rotation about a position wherein the interior of said ring is in communication with the interior of said chamber, said means being adapted to be surmounted by a dental chair;

a support member, carried on said ring for rotation with said ring, that is adapted to mount a dental unit; and power conducting means for interconnecting a dental instrument of the unit to be mounted on said supporting member to at least one service connection positioned in said chamber,

said conducting means having a point of connection to said support member to be rotatable therewith when said ring is rotated,

said conducting means having a yieldable portion between said support member and said point of connection adapted to prevent rupture of said conducting means when said ring and support member are rotated.

12. A dental apparatus as in claim 11 including:

means mounting said support member on said ring for movement of said support member radially'in order to adjust the radius of rotation of said support memher,

said conducting means including a rigidly reinforced portion connected to said support member to be shiftable radially therewith, said yieldable portion of said conducting means being disposed radially inwardly of said rigidly reinforced portion.

13. A dental apparatus as in claim 11 including:

a dental chair mounted in superposition with respect to said chamber and base ring;

power means in said chair to eifect adjustment of said chair; and

power conducting means extending from said power means of said chair to a service connection in said chamber.

14. A dental apparatus as in claim 13 including:

a dental light supporting means mounted externally of said means for supporting said base ring, said light supporting means being carried on an arm that is swingable to opposite sides of said dental chair;

electrical power conducting means extending from said light supporting means to a point of electrical connection in said chamber;

said means for supporting said base ring being adapted to pass said electrical power conducting means therethrough without interfering with rotation of said base rlng.

15. A dental apparatus comprising:

a chamber defined by a surrounding wall, adapted to contain at least one service connection;

a base means upon said chamber adapted to be surmounted by a dental chair;

a support means having an inner end movably connected to said base means and having an outer end that is adapted to receive a dental unit thereon for movement of the dental unit corresponding to movement of said support means, in order to adjust the dental unit relative to a dental chair; and

at least one service line, disposed on said support means and co-movement therewith, that extends between the inner and outer ends of said support means and has an inner end extending into said chamber to a service connection,

the other end of said service line being adapted for ultimate connection to a dental instrument to be carried by a dental unit to be mounted on the outer end of said support means.

16. A dental apparatus as in claim 15 in which:

said inner end of said support means comprises a ring mounted on said base means for rotation on a vertical axis.

17. A dental apparatus as in claim 16 in which:

said ring has its inner edge disposed for communication with said chamber,

said support means including an arm extending radially outwardly from said ring,

said ring and said arm being adapted to, at least partially, house a portion of said service line that is disposed thereon, said service line extending radially inwardly beyond said ring to a point of connection in said chamber.

18. A dental apparatus as in claim 15 in which:

said support means mounts a dental unit support member, at the outer end of said support means, that is adapted for shifting said support member along said support me'ans toward and away from a chair to be mounted on said base means, for orienting a dental unit that is to be carried on said support member with respect to a chair,

said service line being connected to said support member for movement therewith.

19. A dental apparatus as in claim 15 in which:

said support means mounts a dental unit support member, at the outer end of said support means, adapted to pivotally mount a dental unit for turning of the dental unit about at least one axis to orient a dental unit that is to be mounted on said support member with respect to a dental chair to be mounted on said base means,

said service line being adapted to yield to pivotal movement of the dental unit.

20. A dental apparatus as in claim 15 in which:

said outer end of said support means carries an upwardly extending dental unit that is movable by movement of said support means for adjusting said dental unit relative to a dental chair that is to be mounted on said base means.

21. A dental apparatus as in claim 20 including;

a dental chair mounted on said base means,-

said chair having a power means to effect adjustment of said chair, and

power conducting means extending from said power means, through said base means, to a point of service connection in said chamber,

whereby orientation of said chair and said dental unit with respect to one another can be eifected byv selective adjustment of said support means and said chair.

22. A dental apparatus as in claim 15 including:

a dental chair mounted on said base means,

said chair having a power means to effect adjustment of said chair, and

power conducting means extending from said power means, through said base means, to a point of service connection in said chamber, 1

whereby orientation of said chair with respect to a dental unit to be mounted to said outer end of said support means can be eflected by selective adjustment of said support means in said chair.

I References Cited UNITED STATES PATENTS JAMES T. MCCALL, Primary Examiner US. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,524,676 Dated gust 18, 1970 Francis E. Cocherell et a1. Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 12, claim 1, line 56, "is" should read its Column 14, claim 11, line 1, after "about a" insert vertical axis and in a same column 14, claim 15, line 63, "and" should read for Signed and sealed this 13th day of April 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents FQRM P0-1050 (10-691 USCOMM-DC 60376-p59 9 \LS, GOVERNMENT 'RHII'ING OFFICE II! 0-366-384 

